Eggs are generally known to be a nutrient-rich, highly digestible food. Recently, concerns over the high incidence of heart disease in developed countries have led to the identification of risk factors that may be controlled to reduce the incidence of heart disease. One such risk factor is hypercholesterolemia, i.e., high blood cholesterol. In the United States, the Government and the American Heart Association, as well as the majority of experts, have identified dietary cholesterol as a significant contributor to hypercholesterolemia and cardiovascular disease. As a result, it is generally recommended that cholesterol intake should be limited to less than 300 mg per day. Since egg yolks typically contain 213 mg of cholesterol, diets most commonly recommended for hypercholesterolemic patients restrict total egg yolk consumption, including eggs used in baked goods and pasta, to four or fewer egg yolks per week.
Generic chicken eggs typically contain, on average, 25 .mu.g of iodine per whole egg and 0.7 mg of vitamin E. The product of the iodine and vitamin E content is thus 17.5 .mu.g-mg. In addition, saturated fatty acid comprises approximately 37-38% of the fatty acid content of generic eggs.
U.S. Pat. No. 4,187,294 teaches increasing the amount of iodinated amino acids in eggs by feeding hens an increased amount of calcium iodate, in excess of 230 .mu.g/kg of feed. This causes iodinated amino acids to accumulate in the eggs at a level of 7 parts per million (ppm) or more. The eggs are alleged to be effective in preventing and curing hypercholesterolemia.
U.S. Pat. No. 4,394,376 discloses feeding hens an iodine compound and/or seaweed such that the feed iodine content is increased to 50-2,500 ppm. The eggs obtained have an iodine content of 300-4,000 .mu.g per egg, compared with 6-30 .mu.g for conventional eggs. It is alleged that ingestion of the eggs reduces serum triglycerides. Canadian Patent 1,115,983 contains a similar teaching.
U.S. Pat. No. 4,410,541 discloses increasing the monoiodohistidine content of fowl eggs by feeding birds an iodine compound or seaweed. Ingestion of the eggs is alleged to lead to heightened high-density lipoprotein in the blood, decreased plasma triglyceride, heightened lipoprotein lipase activity, and decreased blood cholesterol. The eggs contain 250-3,500 .mu.g monoiodohistidine, per egg.
U.S. Pat. Nos. 4,197,293, 4,197,294 and 4,128,640 describe a reduced cholesterol egg obtained by feeding poultry a mixture of vegetable materials containing a specified amount of iodine, niacin, hormones and trace amounts of calcium and magnesium.
U.S. Pat. No. 5,012,761teaches feeding chickens a composition including fish oil, which results in production of eggs containing substantial quantities of .omega.3-polyunsaturated fatty acids. The modified eggs, when fed to humans, allegedly result in reduction of serum cholesterol, serum triglycerides and blood pressure.
U.S. Pat. No. 4,738,853 teaches feeding hens or other domesticated birds a supplement containing .gamma.-linolenic acid, or higher acids in the n-6 series to reduce egg cholesterol content and increase polyunsaturated fatty acid content. U.S. Pat. No. 4,868,001 discloses an animal feed containing heat-treated .omega.6-unsaturated fatty acids, such as .gamma.-linolenic acid, to improve feed efficiency and animal health.
U.S. Pat. No. 3,657,423 discloses a chicken feed composition containing fly ash for achieving weight gain. The feed also contains various vitamins and trace minerals, including vitamin E and iodine.
While amounts of iodine and fatty acid have been separately varied in egg production, eggs have not been produced wherein the saturated fatty acid, iodine and vitamin E content are controlled to result in a product which is compatible with a lowfat diet. What is needed is an egg which is compatible with low fat diets designed for hypercholesterolemic patients, which may be consumed in substantial quantities without resulting in an increase in the blood cholesterol level of such patients.